Nutinelse2do, I wanted to touch on the Aqua Hot/Hydronic heat systems.
We had the larger Aqua Hot system in our 2008 Monaco Dynasty (42 ft. w/tag). The upgraded AH had the two stage electric elements along with the diesel fired furnace. We only had one problem with the unit in the 7.5 yrs. that we owned it which was not the fault of the system.
We had a kitchen drain hose sprout a leak that just happen to run down a hose into the AH compartment shorting out the AH board. Once all was corrected, the system worked smooth as silk. We had the unit serviced ever 'other' year that included a new fuel filter and nozzle (they also blew-out the chamber). The endless hot water and the even heat from the system is really nice.
(Tag Axle Tires)... The expense of tag tires is fairly minimal. You will change all the tires between 7-10 yrs. (I would replace at 7 but Michelin says you can go to 10 with inspections). So, an extra $1,600 every 7 yrs. is really not bad from the benefits of a tag (stability, extra cargo carrying capacity, extra braking, etc.).
Good luck,
MM.